As a method of charging for packets transmitted in a network, when a device which is an actual charging point, transmitted or received packets, it is charged on the basis of amount of the packets transmitted or received. For example, PTL 1 discloses a technique in which a router that transmits or receives packets to or from a connectionless computer network has a charging information table that stores the number of packets and the number of bytes for each destination address and performs a charging process on the basis of the charging information table.